What The Yell-Ow... I've Been SLIMED!

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As I pulled into my driveway and glanced around the Drapescape, I noted brilliant yellow patches of flowers had appeared.  They seemed to be scattered around, extremely low to the ground and close to the base of a rose bush.  As I got closer to the yellow patches, I started laughing because I realized that had just been SLIMED!  I had what is commonly referred to as dog vomit fungus slime mold on the mulch.  To be accurate, this slime mold, Fuligo septica, is commonly known as “scrambled egg slime” and I could definitely see how it got its name.  Fuligo septica is one of the largest of all slime molds and is conspicuous because of its size and intense yellow color.  This very common organism is established worldwide and is most often found in our landscapes on bark mulch.


Scrabled eggs slime mold, dog vomit fungus
Sudden appearance of Fuligo septica on mulch


The first description of Fuligo septica was provided by French botanist Jean Marchant in 1727, who referred to it as "fleur de tan" or bark flower; enthralled by Fuligo septica, Marchant also classified it as "des éponges" (one of the sponges).  On the other hand, Carl Linnaeus, the Swedish botanist, gave it the latin name of Mucor septicus which literally means septic mucus!


Scrambled eggs slime mold
Fuligo septica a slime mold on mulch in the landscape


Intriguingly enough, slime molds are not true fungi but are found in many of the same sites and locale as fungi.  In fact, slime molds were considered for many years as a special group of fungi but are now classified as Myxomycetes.  This group of ameboid protists, also called plasmodial slime molds, now form part of a group called protostelids in the kingdom Amoebozoa!


Scrambled eggs slime mold on mulch
Fuligo septica a slime mold commonly called "scrambled eggs slime mold"


Slime molds form structures called plasmodia which are naked (i.e., without cell walls) gelatinous masses of protoplasm which can move in an amoeboid manner.  This vegetative stage, termed plasmodium in the life cycle of this organism, allows the slime mold to expand out into its surroundings.  The slime mold plasmodia pulse and ooze around and over surfaces of materials.  The slime mold feeds on bacteria associated with decaying plant material, in addition to spores of fungi, protozoa and particles of non-living organic matter.


Scrambled eggs slime mold


At some point, the plasmodia convert into spore-bearing structures termed an “aethalium”.  Fuligo septica is known for its rather large, spreading aethalium, which has been described as “similar to what a dog might vomit after sneaking off with and eating an entire lemon sponge cake”!  This stage of the slime mold is the spore-releasing or reproductive phase.  As the aethalium breaks down and begins to decay, the surface seems to alter and dark dust (spores) may be noted when it is disturbed.


Aethalium of Fuligo septica
Aethalium (spore bearing structure) of Fuligo septica or scrambled eggs slime mold


No worries about the slime mold because it is not toxic or dangerous to humans, animals or plants.  Yes, it is ugly… but kind of cool too and perfectly normal in a healthy, woodland environment!  I know, I know, “it’s fine out in the woods, but not in my yard on the mulch…That’s just disgusting!”  Well then, just scrape it up and throw it in the trash or in the compost bin but most likely it will come back, as it should… remember “Nature isn’t nice!”


Aethalium (spore bearing structure) of slime mold
Aethalium (spore bearing structure) of Fuligo septica or scrambled eggs slime mold